Kroppsväggar

Kroppsväggar refers to the outer boundary of an organism's body, separating its internal environment from the external world. In multicellular organisms, this concept encompasses various structures. For animals, the body wall typically consists of the skin, which is a complex organ made up of different layers including the epidermis and dermis. Beneath the skin, muscles and connective tissues also form part of the body wall, providing structural support and facilitating movement. In simpler animals, like cnidarians (e.g., jellyfish), the body wall is often a simpler two-layered structure called a diploblastic wall, consisting of an outer epidermis and an inner gastrodermis, separated by a jelly-like mesoglea.

In plants, the body wall is a more rigid structure. The outermost layer is the cell wall, primarily composed of cellulose, which provides structural integrity and protection to plant cells. Above the cell wall, plants often have a cuticle, a waxy layer that helps prevent water loss. The collective tissues forming the outer covering and supporting structures can be considered the plant's body wall.

For microorganisms like bacteria and fungi, the body wall is the cell wall, a rigid layer outside the cell membrane. This bacterial cell wall is typically made of peptidoglycan, while fungal cell walls are composed of chitin. These structures are crucial for maintaining cell shape and preventing osmotic lysis. The concept of a body wall is thus fundamental to understanding organismal organization and interaction with their environment across the biological spectrum.